Micrometer.



CHARLES E. JOHNSON, F MUSKEGON, MICHIGAN, ASSIGNOR TO MUSKEGO lSPECIALTIES COMPANY, 0F MUSKEGON, MICHIGAN.

MOTOR 'MIGBOMETEIL ASpecification.uf Letters Patent. l' Patented Oct, 11,v '1910.

. Application ined Aprile, 1910. serial No. 554,563.Y

To all whom it may concern:

Be it known that I, CHAnLns E. J omasex,

.a citizen of the'United States, residing at.

Muskegon. in the county of Muskegon' and` State of Michigan, have lnvented certain new, and useful Improve-ments in Micrometers, of

" whichthe following is a specifcation.

My invention relatesto improvements in implements forv measuring very small dierences in the size ordiameter of objects for the purpose of determining Vto the minutest `fraction of, an inch, the diameter. or dimen sions of an object, and its objects are: First,

" to provide a micrometer that may be so con-y nected ii-'iti'. a lathe or grindingmachine as to determine the smallest possible fraction of an inch or' difference in the diameter of any sha t or other object. being worked thereon. Second, to provide a micrometer or implement ot' the'liind stated with which a shaft.- having an uneven surface may be ground to the exact dimensions and proportions desired Y without being taken from the grinding machine and without stoppingfthe Jmachine,

and, third, to prov ide an implement of the kind stated with which the minutest imper- -i'ections in the surface of shaft, or other article being ground, may be instantly detected without. stopping the machine.` kI at# tain these rohjeetsby the-mechanism illus-r trated in the accompanying drawing, in Which- Figure L is a side elevation of the micrometer shown' upon a grinding machine with the working parts cut otll on the line 1--1 of Fig. 3. Fig. 2 is a plan of a grinding machine. with the micrometer attached. Fig. 3 is an elevation of the saine. Fig. L is a side elevation of the micrometcr-showin;lr an ex' metlingly fine adjusting mechanism for turnf, ing perfectly round rods. Fig. 5 is a front, elevation of the same, and Fig. ti is a front., elevation of the same constructed for malt'-A measurcments upon rods or shafts having uneven surfaces.

Similar letters refer to similar parts throughout the several views.

Thisimplement consists of a lower, permanentarm A that I prefer to have made integrai with a semieircular bearing portion C' to which the handle C is secured. T he boaring poriion C is adapted to rest, freely upon a gui-.lin rod D so that the implement may be rocln freely up and down, with this rod as a pivm. point. To the arin A is pivotcd a second arm, B, as at a, in such a manner thatthe outer ends of the arms, as at v[-1 H, 'may be :made to recede `from er approach' cach other as the surface of `the object being` vxu'rorked may vary. 60

H H represent two thoroughly hardened jaws that are secured into or onto the ends of the arms A and B in position to properlycaliper a shaft or rod, as L, that is'being Ground. These jaws H, H, are made adjustable as indicated by. the slots h so that they may vbe adjusted to various sizes of'` shafts or rods L, and the two arms are actuated to draw the jaws H H strongly .toward each other by anxv'available form of spring. that shown at E 1n Figs. l and 4, being pre'- ferred.

The arm B has, mounted thereon, a standard F which has a segment, F', formed at itsv upper end, which segment is graduated with a very line', accurate scale whereby the diameter or dimension of an object, as L,"rnay be determined to the thousandth of an inch, or less, by noting the position of the end ofthe needle or index G upon the segment, and 'this needle is made 'sensitive to the slightest possibleimperfection in the surface of L as followsz-The needle is pivotall supported on the arm B, substantially as vindicated at G', and has a short lug or arm, as g, projecting out to one side ofthe pivotal line. This erm rests upon the upper end of a small pointed needle K, the other end of which rests upon the long,r end of the lever I -or I. The lever I'is pivotally supported upon a standard J, as at j. and the short end of this' lever receives the fine point of the bearing I1, f or its equivalent., as at z, so thatnnyrvariation in the surface of the shaft L, as it is turning vbetween the jaws 'H ll, is greatly ,magnified'by the movement of the needle (1l `upon thedlal or segment F', soythat the movement of the jaws H H the one thousandth of an inch, or even one half that distance, will be readily detected and measured on the scale on the segment V1?",and as the operator always stands in position to easilyA manipulate the handle C of the micrometer he is. necessarily, in position to casilygnote every' movement of thenccdle. G, and thus always able to determine the exact variation, if any, that exists in the surface of the shaft L as it revolves, and is being;r acted u pon by the fast revolving emcry wheel M.

As 'the operation of grinding machines is side, it is necessary to provide some means well known by those versed in the art, and as they do not enter, in anyway, into the direct operation oi' my invention, I will not Vfiche.' nv atteinpt'at describing one, and simply show parts of one form of these machines for the purpose of illustrating the ac-y tion of this micrometer.

When turning and nieasuringa perfectly instance, the shaftL shown in Figs. 1 and 6,

which have a cam or'projeetion, asl, on one for allowing said projection to pass, with the shaft, between-theb jaws H H without danger ofdisarranging the bearing points and pieces. As, for instance, to throw the jaws as far apartas would be necessary in the action shown in Fig. 6, Vthe needle K' would-be; carried so far by the end of the lever I that it would drop out of the arm B and cause great annyance. To obviate this I place a lon -setfscrew, as. b, in the arm B, that I can a just to any position necessary i for the proper actuating of thev lever I; and

it is designed to have suflicient` length through the arm B to avert; all danger ofy the needle K liecomingA disengaged from its bearing at i on the long end of the lever I or I a shaft with a cani, as Z, on one side, it is necessary tomake the bearing at C broad enough to hold the micrometer to a perfect perpendicular position, as it is necessary to make'the lower jaw' H as thin as possible, hensejI mortise a thin plate H'into the end of the jaw A, us in Fifa 6. but when turning a perfectly straight shaft the lower yjaws may be wider`v and for this purpose a plate, H', may be placed on each'side of the end of the arm A, as indicated in Fig. 5, which will aid greatly .to hold the micrometer to proper position. Y y hWhen using the form of sprmfr shown 1n thcl several views, for desiring the arms A and B toward each othfat. it is necessary to forni some kind of integral lugs, as e, upon j for actuating the finger.

the arms, for the spring to act upon, vas indicated in Figs. l and 4.

The lug or arm g, that controls the inovenient of the needle G maybe held in contact with the needle K by means ofy a very delicate spring, as g,shown in Fig. 1.

by Letters Patent of thefUnited States, is:

1,` In a mircometer, a; permanent arm, an arm. pivotelly, connected therewith, a spring for holding said arms to normal position, a handle on the* permanent arm, a guide way betweenthe handle and the pivot point betweenthe arms,`adjiistable jaws at the ends of the arms; a standardhaving an indexed segment at its end, a finger parallel .with the standard, a lever secured between the arms, and connections between the arms and said lever, and between the lever and the linger 2. In a mlcrometer, two arms pivoted to- .and desire to secure gather near one end, s spring forr holding said arms to normal pesition, a handle con-:

nected with one o said arms, a bearing surface between the lia-nale` and `the, arms, jaws connected with the other ends of the arms,

a-standard on one arm having an indexed f segment. at its upper end, a finger pivotally supported on the arm parallel"V with the standard, a :'hort arm at. ri ht angles with said linger, a lever pivot-ally supported from the lower arm, a. needle between` said lever and the short arm on the finger,- and a connection between said lever and the upper arm ofthe micrometer, all 'arranged to actuaie the finger bythe movement of the jaws vand arms and to greatly increase said moveo v l `ment at the end of said finger. When using this micrometer for turning 3. In a micrometer, a permanentV arm, a movable arm pivoted thereto, jaws 1n the free ends of said arms, vmeans for holdin said arms to normal positioin'a standard on the movable arm, a finger pivoted on said ai'in to stand parallel with the standard, a lever pivotally supported between the arms, an'adjiisting screw, and' a needle connected with said lever for actuating said finger one way, and a springfor actuating itthe other way for iiie measurements.

,Signed at Muskegon Michigan March 26 una` CHARLES E. JOHNSON.

' presence -of L. O. Goin-,03, C. L. Cmusinamni.

los 

